Clear Airway Apneas

I understand obstructive and hypopneas but am not sure what a clear airway apneas is and why it wasn't recorded during my in hospital sleep study? The clear airway apneas are the highest number in my morning AHI report. I have my hypo and obstructive down pretty low, but I have had as many as 67 clear airway events in a sleep. Should I be concerned?

Yes, you should be concerned. A clear airway is an event where there is no breathing but the airway is open. That is essentially a central apnea by a slightly different name. The CPAP manufacturers use the clear airway term because that is essentially what they know from the machine. The airway is clear and there is no breathing for 10 seconds or more.

The objective is to get the total AHI including clear airway events under 5 per hour. I would suggest discussing these results with your sleep doctor as I would suspect having 67 in a night is probably putting the AHI over 5?

Another option would be to download SleepyHead and look at the detailed results for the night. It requires a SD card reader, and a PC or Mac to install the free software. There is a way to copy the daily report and post it here if you want comments on what the issue may be. One problem could be the use of too much pressure, but each case tends to be a little different. In general more pressure is good for reducing obstructive apnea, but may increase central or clear airway apnea. Also use of EPR can aggravate central apnea too in some cases.

There is also a condition called treatment emergent central apnea where no or little CA is identified in the sleep study but it emerges with CPAP treatment. In most cases it goes away after 6-8 weeks.

Thank you. My SD card went bad and I am waiting for my provider to send me a new one. I see my Doc middle of the month and I am looking forward to seeing if he agrees that therapy is working well for me. For the most part, my AHI has been less than 5.5 as low as 2.6 and as high as 7.7 but mostly around 5 - so I feel pretty good.